Final answer:
The distance between town A and town B is approximately 6,726.5 kilometers.
Step-by-step explanation:
To find the distance between town A and town B, we can use the latitude and longitude coordinates of both towns. First, convert the longitude difference of 40° (30°E to 10°W) to kilometers. Since the Earth's circumference around the equator is approximately 40,075 km, each degree of longitude is about 40,075 km / 360° = 111.32 km. Therefore, the longitude difference between town A and town B is 40° * 111.32 km/° = 4,452.8 km.
Next, find the latitude difference of 47° (51°N to 4°N) and convert it to kilometers. The distance between each degree of latitude is approximately 111 km. Therefore, the latitude difference between town A and town B is 47° * 111 km/° = 5,217 km.
Finally, use the Pythagorean theorem to find the straight-line distance between town A and town B. By treating the longitude and latitude differences as the sides of a right triangle, the distance between town A and town B can be calculated as sqrt((4,452.8 km)^2 + (5,217 km)^2) = 6,726.5 km.